Disk2vhd: Virtualize Existing Systems
Rebuilding a working system from scratch can be time consuming, because of that its a good idea to use P2V or Physical to Virtual tools that automate the process for you. One of them is Disk2vhd by Sysinternals created to ease the transition process from baremetal to virtual with a few clicks. This P2V tool works by creating a virtual image of the system its running on and the result is a VHD file(Virtual Hard Disk - Microsoft’s Virtual Machine disk format) which can be use in Microsoft Virtual PC or Microsoft Hyper-V . 
Disk2vhd is easy to understand and use. You can download Disk2vhd free of charge from the Sysinternals site. 
Note: Due to the hardware changes you may need to reactivate the operating system once again.
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disk2vhd, microsoft, sysinternals, windows — Jun 7, 2010